Abstract: A multistage wheel drive includes primary and secondary planetary stages, in which the ring gear of the primary (i.e., input-side) planetary stage is formed from a single machined part which also includes the planet gear carrier of the secondary (i.e., output-side) planetary stage. This dual-function “combination” component includes a splined exterior surface which interfaces with a correspondingly splined interior surface on the spindle in order to rotationally fix the combination component to the spindle. This arrangement ensures concentricity between the primary and secondary planetary stages, while allowing a desired amount of radial tolerance between the spindle, the combination component, and the hub of the wheel drive. In addition, the present arrangement can be produced efficiently and inexpensively.

Abstract: An apparatus with an electric motor including a stator and a rotor; a shaft secured to the rotor; a gearing assembly coupled with the shaft; and a housing assembly defining a non-partitioned interior space housing both the electric motor and gearing assembly. The shaft may be unsupported by bearing assemblies and/or free of oil seals and similar sealing engagements between the electric machine and gearing assembly. The motor may be an axial flux motor having a single stator. The gearing assembly may be a planetary reduction gear assembly with a sun gear mounted on the shaft. The apparatus may include only a single electric motor or include a second electric motor and second gearing assembly. The embodiments having a single motor may be used to drive a fan or a vehicle wheel. The embodiments having two motors may be used as a differential drive.